Struct Cache 

pub struct Cache { /* private fields */ }

Per-vendor cache directory and helper API.

Construct with Cache::for_vendor; the directory is created lazily.

Implementations

impl Cache

pub fn for_vendor(vendor: &str) -> Result<Self>

Build a cache rooted at ~/.cache/ai-usagebar/<vendor> (or under $XDG_CACHE_HOME when set).

pub fn at(path: PathBuf) -> Self

Cache rooted at an arbitrary directory — for tests.

pub fn ensure_dir(&self) -> Result<()>

Ensure the directory exists. Safe to call repeatedly.

pub fn dir(&self) -> &Path

pub fn payload_path(&self) -> PathBuf

pub fn stale_path(&self) -> PathBuf

pub fn last_error_path(&self) -> PathBuf

pub fn lock_path(&self) -> PathBuf

pub fn payload_age(&self) -> Option<Duration>

Age of the payload (None if it doesn’t exist). Used by the widget to decide whether the 60s cache window applies.

pub fn fresh_payload(&self, ttl: Duration) -> Result<Option<Vec<u8>>>

Returns the cached payload only if it is younger than ttl. Used as the fast path in _fetch_usage (claudebar:343-349).

pub fn maybe_payload(&self) -> Result<Option<Vec<u8>>>

Read the payload regardless of age. Err if the file exists but is unreadable; Ok(None) if it just doesn’t exist.

pub fn write_payload(&self, bytes: &[u8]) -> Result<()>

Atomically write a new payload. Uses tempfile + persist (POSIX rename), matching claudebar’s mktemp + mv invariant.

pub fn mark_stale(&self)

Mark the cache as stale. Idempotent.

pub fn is_stale(&self) -> bool

pub fn write_last_error(&self, code: u16, msg: &str)

Write the .last_error marker — first line code, second line msg. Best-effort, never errors (matches claudebar:478-486 which silently continues if the cache dir isn’t writable).

pub fn read_last_error(&self) -> Option<(u16, String)>

Trait Implementations

impl Clone for Cache

fn clone(&self) -> Cache

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Cache

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.